Telephone system



Jan- 6, 1942 R. B. MQCOWN ET AL 2,269,375

TELEPHONE SYSTEM R. B. MC COWN l /N VE /V T0195 H. SCHNECKLOTH By R. W SMI TH ATTORNEY R. B. MccowN IE-r A1. 2,269,375

TELEPHONE SYSTEM Filed Aug. ll, 1939 2 Sheets-Sheet 2 )f ATTORNEY l EIIIIIHI' R B MC COWN R. W SM/ TH "-mlli FILIMUHH Em ,EN \N Jan. 6, 1942 Patented Jan. 6, 1942 UNITED STATES PATENT OFFICE TELEPHONE SYSTEM Application August 11, 1939, Serial No. 289,674

12 Claims. 4 (C1. 179-63) The objects of the invention are to improve the 5 service available to the patrons of coin line stations; to simplify the duties of the operators in the establishment of connections involving paystation lines; to minimize as much as possible the equipment for disposing of the deposited 10 coins; and to effect other improvements in systems of this kind.

It has been the practice in the past to provide equipment in the coin trunks at the central oice for disposing automatically of a coin deposited l5 by the calling patron for a call which he estabvlishes with his dial over automatic switches to a subscribers line, the coin being collected or refunded automatically depending on the success of the call, and to provide further equipment zo.

` to a system using any particular kind of switchwhereby the operator, when the calling patron extends the connection to her position, may dispose of the coins deposited by him at her request.

According to the present invention the equipment heretofore provided for enabling the opera- 25 tor to dispose of deposited coins is dispensed with,

`and means is provided for disposing of all deposited coins automatically, both for connections which the calling patron completes with his dial and for connections established with the assi'st- 30 ance of the operator.

A feature of the invention is a system in which a coin control mechanism discriminates between position. If the call is made to another subscriber without the assistance of the operator, f the coin control mechanism disposes of the coinl in the usual manner when the connection is re-f' 4Q of the line finder switch F. The finder F is associated with a first selector switch S-l which, `together with succeeding switches, such as seleased, collecting it if the call was successful'or refunding it in the event the called partly did not answer. If, however, the calling patron dials for the operator to assist him, the coin control mechu anism, having distinguished the nature of the@45 call, proceeds at once to refund automatically the initial coin deposited by the patron for the purpose of making the call and sets itself in condition to collect later, when the connection is released, any coins that may subsequently be 5f 50 operator by the patron at the station of a coin5`5 line to which the operator has extended a connection over a train of automatic switches, are collected automatically when the connection is released without any further act on the part of the operator.

The foregoing and other features of the invention will be discussed more fully in the following detailed specification.

In the drawings accompanying the specification:

v.Figure 1 discloses a pay station line extending to the central office and terminating in a coin control mechanism; and

Fig. 2 discloses a line finder switch, in which the pay station line appears, together with selectors and connectors for extending calls to subscribers lines and also to the operators position. rThis ligure also illustrates a connection established to the pay-station line as a called line.

While the invention is not necessarily limited ing mechanism for establishing connections, it has been illustrated for convenience in a system employing switches of the well-known step-bystep type.

The pay-station line |00 is equipped with a coinreceiving and disposal mechanism, including a coin relay IOI, which may be of the usual prepay type or may be of the type shown in the application of F. A. Hoyt, Serial No. 274,129, filed May 17, 1939. The pay-station is also provided with an impulse dial |02 for setting the selective switches in the central office.

At the central oflice the pay-station line is provided with an individual coin control mechanism, which is interposed between the incoming conductors of the line |00 and the usual line and cut-off relays |03 and |04, respectively. The pay-station line, after extending through the coin control circuits, appears in the terminal bank lector S-Z and connector C-|, serves to extend the'pay-station line to a local subscribers line,

1 such as the line 200.

The first selector switch S| also has access through its tenth level terminals to the operators positions, such as position O-l, by way of trunks, such as the trunk 20|.

The pay-station line |00 also appears in the kcontact bank of the connector switch C-Z, over which it is seized as a called line. For example, the operator at position O-Z'may extenda connection to the pay-station line by Way of selectors S-S and S-4 and connector C-2.

The detailed operation of the system will now be described. For this purposes it will rst be assumed that the patron at the pay-station of line wishes to establish a conversational connection with the subscribers line 200. To this end the calling patron deposits a coin |05 in the coin receiving mechanism and removes his receiver from the switchhook. A circuit is now completed from ground through the closed coin contacts |06, windings of the coin relay |0|, thence through the switchhook contacts vtoline conductor |01, lower normal contacts of relays |00 and |09, winding of polarized relay |10, conductor normal contact of cut-off relay |04, winding of line relay |03 to battery. vRelay |03 operates in this circuit and places ground potential on the start conductor ||2 to start the idle line nder F in operation. As soon as the off relay |04 and the winding of sleeve relay ||3 to battery. These relays operate, and the line relay |03 is released. The tip and ring conductors of the calling line are now extended through the brushes of the nder switch F to the impulse receiving relay associated with the first selector switch S-I. The sleeve relay ||3 in operating closes an obvious circuit for operating the slow-release relay |4. The circuits are now ready for the calling patron to transmit impulses.

When the dial |02 is manipulated to send the rst series of impulses to the central office, relay 2|1 responds, and the selector switch S-I is operated to extend the calling line through to the succeeding selector 'S-2. The selector S-2 responds to the second series of impulses and extends the connection to the connector switch C-I. During the extension of the connection from selector S-I to selector `S---2 and thence to connector C-I, the current 'flowing over the subscribers line is in such a direction that the polarized Yrelay ||0 in the coin control mechanism remains inoperative. The calling line is now supplied with current from the connector C-I over a circuit traceable from battery through the lower winding of relay 204, lower normal contacts of relay 205, thence over the lower side of the connection extending back through the calling line loop and returning over the upper side of the connection through the upper normal contacts of relay 205 and the upper winding of relay 204 to ground. Relay 204 operates and closes an operating circuit for slow-release relay 2 |6. Relay 2 I8 places holding ground on conductors 200, 202 and 203. The direction of current through the polarized relay ||0, however, is still such that this relay does not operate. The next two series of impulses operate the connector switch C-l to complete the connection to the called subscribers line 200.

When the called subscriber answers, a circuit is closed for operating relay 205, and this relay causes a reversal in the direction of current flowing over the calling line |00. Current flowing in the reverse direction operates the polarized `closed contacts of relay relay ||0 in the coin control circuit. When relay |0 first operates, it closes a circuit from battery through the winding of charge relay ||5, contacts of relay ||0 through the right high resistance winding and the left low resistance Winding of relay IIE to ground. Relay ||5 does not operate in this circuit, but relay ||6 energizes and closes its contacts after a measured interval determined by the dash-pot ||1. This interval vis provided to insure that the operation of relay ||0 is caused by the answer of the called subscriber and not by a momentary reversal of current or other disturbance in the connection. When the relay ||6 closes its contacts, a short circuit is closed around the high resistance winding, and relay ||5 now receives sufficient current to operate. Relay ||5 when operated locks through its own lower contacts to ground at the ||4. The established connection is now in condition for conversation.

At the termination of conversation the receivers are replaced on the switchhooks at the `calling and called stations, and relays 204 and 205 of the connector switch are released. Ground potential is removed from the holding conductors 206 and 202 to initiate the release of the line iinder, selector and connector switches. The removal of ground potential from the sleeve conductor 203 also causes the release of cut-off relay |04 and sleeve relay ||3 in the coin control circuit. Relay ||3 closes a circuit from ground through its back contacts,closed contacts of relay ||4, which remains operated for an interval following the release of relay ||3, front contacts of slow-release relay ||5 through the winding of the coin collect relay |00 to battery. After an interval relay ||4 releases and opens the circuit of relay |08 and also the locking circuit of relay ||5. During the interval measured by the release time of relay H4, relay |08 applies current from the positive pole .of the coin collect battery ||8 to both conductors of the line |00. This current flows through the windings of the polarized coin relay |0| and operates it in the proper direction to collect the deposited coin |05. The equipment is now restored toits normal condition in readiness for the next call.

If the called line 200 is found busy or the called subscriber fails to answer when ringing current is applied to his line, relay 205 remains deenergized and no reversal of current occurs. Hence the polarized supervisory relay ||0 does not operate, and no circuit is closed, for the operation of the marginal charge relay ||5. When, therefore, the calling party hangs up his receiver and relay I3 releases, a circuit is closed from ground through the upper contacts of relay H3, upper contacts of slow relay ||4, upper back contacts of relay ||5 through the winding of relay |00 to battery. Relay |09 energizes and connects the negative pole of the coin refund battery |2| Ato the Vconductors of line |00. Current `from the source |2| operates the coin relay |0| in the proper direction for refunding the coin to the calling party.

Similarly, if a call is made from the pay station for which no charge is necessary, the circuits may be arranged in any well-known manner to omit the current reversal and the operation of the polarized relay I0. Consequently the deposited coin is refunded to the lcalling party when he replaces his receiver on the switchhook. i Assume next that the patron at the Apay station of line |00 wishes to make a toll call needing the assistance of the 'operator vat'position O-|.

iaacaszs d'3 To re'a'ch the operator the calling patron' deposits a coin |05, removes his receiver from theswitchhook, and manipulates his dial |02 to transmit a series of ten impulses. YThedeposit of .the/coin and the removal of the receiver cause vthe opera- 55 tion of line .relay |03, which in turn causes the line iinder F to seizethe pay-station line |00. The transmission of the series vof. ten. impulses results in the operation of the ,selectorLswitch S| .toits tenth level of terminals. J The selector ,3m S-I hunts in this level and seizes an idle trunk 20| extending to the position O-I. f When the shaft of the selector S--l advance to the tenth level, it closes the levelcontacts 201 to send a discriminating signal back to the .coin .15 control circuit identifying the call as onethat is being extended to the operators position. The circuit for transmitting this signal may betraced from ground through the contacts 201, conductor 208, through the lowermost brush ofthe linelzo iinder F, conductor 209, through the windings of relays ||9 and |20. Relay |20 operates immediately, but relay ||9 is slow to act and does not close its contacts until an interval has expired following the operation of relay |20. Relay,-.25

contacts of the sleeve relay ||3. Relay |20 alsa-f3()V Amatic switches, such as .selectors S-3 and S-v-4 and connector C-Z, `from an operators position closes an obvious circuit for the coin return relay |09 and applies ground potential to the sleeve conductor 203. Relay |09 disconnects the tip and ring-conductors of the line r| from the connection extending toward the line iinder and con-,35 Lnects these conductors to the negative pole of coin refund battery |2|. During the time the line |00 is disconnected from the line nder by the relay |09 the sleeve relay H3, the cut-off relay |04, and the operated switches F andl S-'I ..40

relay operates in the proper direction to refund5 the coin |05 to the calling patron. After the measured interval expires, the slow-operaterelay I9 attracts its armatures and closes a short circuit around the winding of relay Relay |20 being slow to release maintains its contacts .applies ground potential in the usual manner to closed for a further interval after the operation of relay ||9. At the end of this further interval relay |20 releases and opens the circuit of the collect relay |00. Relay |09 disconnects the coin refund battery |2| from the line and recloses the,55

talking conductors of the extended connection. Thus the coin control mechanism distinguishes a call that is being made to the operators position, refunds the initial coin immediately, and

operates the charge relay ||5 to prepare fory them() automatic collection, at the end of conversation,-` of any coins that may subsequently be deposited at the pay station. f

The operator at position O-l responds tothe call by inserting the answering plug of her cord65 amount necessary to cover the charge for the particular call requested. When the called party I answers, the usual supervisory signaliis displayed at the operators position; but it'isno'tnecessary 75 ycircuit from the trunk 20|.

l She also requests the. Vcalling. patron to deposit in the coin vbox the o'nthis'type of c'all'to reverse the current flow- 'ing vb'ackover the connection through the polarized relay ||0 andthe calling line |00. It isnot necessary to reverse the current because. the

`charge relay ||51in the coin control circuit has 4already operated asexplained by reason of the `fact that the connection was extended to the operators position. Furthermore, the coin control -circuit is set to collect any coins that may *be deposited at the request of the operator.

At` the end of conversation the calling patron replaces his receiver on the switchhook, and the operator obtains the usual supervisory signal, whereupon she proceeds to disconnect her cord The line iinder and selector switches release .and groundpotential is removedfrom vthe sleeve conductor 203 permitting the release of relays |04 and ||3.A Relay ||3 closes a circuit through its back contacts through the closed contactsv of slow-release re- ',lay ||4 through the front contacts of the operated charge relay ||5 and thegwinding of @coin collectrelay |08 to battery. Relay |08 Aapplies the collect battery ||8 tov the line, and the deposited coins at the substation are collected. After an interval the slow-release relay ||4 releases, releasing in turn the charge relay ||5 and collect relay |08.

Assume next that a connection is extended to thepay-station line |00 overa train of autoator ywho has finally succeeded in setting up a .delayed call to a subscrbers line at .the request of the patron at the pay-station of line |00V and she no w callspay-station line |00 over the selector and connector switches. Since the patron .of the pay-stationline v|00 has initiated the call rit will be necessary for him to deposit the requested coins, which should kbe collected at the end of conversation. `To this end the direction of current supplied-from the connector switch C-2 over the called pay-station line |00 is such vthat the relay ||0 operates when the patron at the pay-stationremoves khis receiver. The operator at position O-2, by means ofthe usual impulse dial, sets the selectors S--3 and yS| and the connector C-Z on the terminals yof the pay-station line |00. The connector switch C-2 the sleeve conductor 2M., causing the operation of cut-off relay |04 and sleeve relay ||3. The

line is signaled in the usual manner, andthe party at the pay-station `replies by removing the receiver' from the switchhook. vWhen he removesA his receiver, a circuit is closed for supplying current frornthe connector C-2 to the `line |00 through a current supply relay similar to the relay 205 illustrated in the connector switch C|./ It will be noted from inspection thatthe current supply circuit extends from the negative pole of battery over the upper winding of the relay (corresponding to relay 205) thence over the tip conductor of the connector switch .C-'-2, conductor 2|2 to the tip conductor |22 deposited the lamount requested by the operator `the parties are free to proceed with the conversation.

At the end of conversation the switches S3, S--ll and C--2 are released, and holding ground potential is removed from the sleeve conductors 2M and 233. Relays |04 and II3 release, and a circuit, .hereinbeiore traced, is closed for operating the coin collect relay |08 to eiect the -collection of the coins deposited at the pay-station.

What is claimed is:

1. In a telephone system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, a subscribers line, an operators position, an automatic switch, means responsive to the deposit of a coin in said .device for extending said pay-station line to said automatic switch, means responsive to impulses sent over said pay-station line Afor Vdirectively operating said switch to extend a call either to said subscribers line or to said operators position, discriminating means individual to said 4paystation line and dependent on the impulses transmitted for determining whether the call is being extended to said subscribers line or to said position, and means controlled by said discriminating means for automatically refunding the deposited coin.

2. In a telephone system, a pay-station ivline, an impulse sender and a coin receiving device -at said pay-station, a subscribers line, an operators position, an automatic switch, means responsive to the deposit of a coin in said device for extending said pay-station line to said -au- `tomatic switch, means responsive to impulses sent over said pay-station line for directively operating said switch to extend a call either to said subscribers line or to said operators position, discriminating means dependent -on the number of impulses sent over the pay-station line for determining Whether the call is being extended to said subscribers line or to said position, and means controlled by said discriminating means for refunding the coin deposited in said receiving device and for collecting any subsequently deposited coins at the termination of the call.

3. In a telephone system, a pay-station line,

an impulse sender and a coin receiving device at` said pay-station, a subscribers line, an operators position, an automatic switch, means responsive to the deposit of a coin in said device for extending said pay-station line to said Aautomatic switch, means responsive to impulses sent over saidpay-station'line for directively operating said switch to extend a call either to said subscribers line or to said operators position, discriminating means controlled by said automatic switch for determining whether the call is extended to the subscribers line or to said operators position, and means controlled by vsaid discriminating means when a call is extended to said position for refunding the deposited coin immediately and preparing for the subsequent collection of any coins deposited thereafter at the request of the operator.

4. `In a telephone system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, a subscribers line, an operators position, an automatic switch, means responsive to the deposit of a coin in said device for extending said pay-station line to said automatic switch, .means responsive to impulses sent over said -pay-station line for directively operating scribed. After the patron at the pay-station has said switch to extend a call either to said subscribers line Aor to said operators position, discriminating means dependent for its operation `upon the rextent of movement of said automatic switch for determining when a call is being extended to said operators position, means effective at the'termination of a call to said subscribers line .for collecting or refunding a deposited coin, and means controlled by said discriminating means when `a call is extended to said position for refunding 'the deposited coin immediately and for collecting subsequently any further coins that maybe deposited thereafter at the request of the operator.

5. In a telephone system, a line having a paystation thereon, an impulse sender and a coin receiving device at said pay-station, a coin control mechanism associated with said line, an automatic switch, means responsive to the initiation of a call 'at saidipay-station for extending said line to said switch, a subscribers line, an operators position, means responsive to impulses transmitted over the pay-station line for operating said automatic switch to extend a connection .either to the subscribers line or to said operators position, -means responsive to said coin control mechanism Aupon the release of a connection extended to said subscribers line for disposing automatically of a coin deposited'in said receiving device, discriminating means controlled in accordance with the directive 'operation of said switch for determining when a call is made to said operators position, and means responsive to said discriminating means for causing said coin control mechanism to refund a deposited coin when the call is made to `said voperators position and for preparing 'said control mechaynism to collect automatically at the termination of the vcall any further coins that may be deposited in said receiving device.

6. In a telephone system, a non-numerical switch, a pay-station line appearing in the terminals of said switch, an impulse sender and a kcoin receiving device at the pay-station of said line, a rcoin control mechanism connected in said line between 'the pay-station and the terminals of said switch, an automatic switch, means responsive to the initiation of a call at said paystation for operating said non-numerical switch to extend the pay-station line to said automatic switch, means responsive to the transmission of impulses over said line for operating said automatic switch to extend calls from said pay-stationline, meansfor rendering said control mech- .anism eiective to dispose `of coins deposited in said receiving device at the termination yof calls extended from said pay-station, other automatic switches for extending -connections to said paystation line, and means responsive to the exten- .sion of a call to said line over said other automatic switches for rendering said control mechanism effective to collect automaticaily a coin deposited in said receiving device.

7. In a telephone system, a non-numerical switch, a pay-station line appearing in the terminals of saidswitch, an impulse sender and a coin receiving device at said pay-station, a coin control mechanism individual to said line and connected therein between said pay-station and theterminals of :said switch, an automatic selector switch, means responsive to the deposit of a coin in said device for operating said nonynumerical switch to extend said pay-station line `to said selector switch, means responsive to impulses transmitted over said line for operating said selector switch to further extend said line, an operators position, other -automaticswitches controlled by said operator for extending a call to said pay-station line, and'means responsive to the extension of a call byj,way of said other automatic switches to said pay-station line for rendering said control mechanism effective to collect a deposited coin upon A`the termination of the call. s

8. In a telephone system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, a subscribers line, an operators position, an automatic switch, a coin control mechanism individual to 'and forming a part of said pay-station line, means responsive to the deposit of a coin in said device for extending said pay-station line to saidI automatic switch, means responsive to impulses sent over said paystation line for directively operating said switch to extend a call either to said subscribers line or to said operators position, means effective when a call is extended to said operators position for transmitting a signalv from said automatic switch to the coin control mechanism in said pay-station line, and means responsive to said signal for'causing said control mechanism to automatically refund the coin deposited at said pay-station. v-

9. In a telephone system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, a subscribers line, an operators position, an automatic syvitch, means responsive to the deposit of a coin in said device for extending said pay-statioir line to said automatic switch, means responsive to impulses sent over said pay-station linefor directively operating said switch to extend a call either to said subscribers line or to said operators position, means at the operators position for answering a call extended thereto, meanseffective when a call is extended to the operators position and independent of the operatorsact in answering the call for sending a signal tofsai-d pay-station line, and means responsive to said signal for automatically refunding the deposited coin.

l0. In a telephone system, a'fpay-station line, an impulse sender and a coin receiving device at said pay-station, a subscribers line, an operators position, an automatic switch, a coin control mechanism individual tofand forming a part4 anism, means responsive to said signal for causing the automatic refund of the deposited coin, and means also operated in response to said signal for preparing said coin control mechanism to collect unassisted by the operator any coins that may subsequently be deposited at the request of th'e operator.

11. In a telephone-system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, subscribers lines, an operators position, an automatic selector switch, a nonnumerical `switch eiective when a coin is deposited in said device for extending said pay-station lineto said selector switch, means responsive to impulses transmitted by said impulse sender over said pay-station line for directively operating said selector switch to extend a call either to a subscribers line or tosaid operators position, means at the operators position for answering a call and for furtherv extending it to a subscribers line, means effective when a call.

is extended to said operators position fortransmitting a signal ,through said non-numerical switch to said pay-station line, means responsive to said signal for automatically refunding the deposited coin and further means responsive to said signal for automatically collecting Without the assistance of the operator or the called party all coins that may subsequently be deposited at the request of said operator.

12. In a telephone system, a pay-station line, an impulse sender and a coin receiving device at said pay-station, subscribers lines, an operators position, an automatic selector switch, a non-numerical switch eiective when a coin is deposited in said device for extending'said paystation line to said selector switch, means responsive to impulses transmitted by said impulse sender over said pay-station line for directively operating said selector switchfto extend a call either to a lsubscribers line or to said operators position, means at the operators position for answering a call' and for further extending it to a subscribers line, a circuit closed by the movement of said selector switch when it is operated to extend a call to the operators position for transmitting a signal through said non-numerical switch to said pay-station line, relay means individual to said pay-station line and responsive to said signal for causing the immediate refund of the coin deposited-at the paystation, other relay means individual to said paystation line andalso responsive to said signal, and coin collect mechanism operable under control of said other relay means for collecting any coins subsequently deposited at said pay-station at the request of the operator.

RAY B. McCOWN. HARRY lHOWARD SCHNECKLOTH. ROBERT W. SMITH. 

